What do you mean by smelting?

To smelt means to heat an ore with a chemical called flux until the metal melts and flows away from whatever it was associated with. In chemistry this is called a reduction, which means the opposite of oxidation. The chemical used for flux might be different for each metal.

The basic guide in this subject is still "De Re Metallica" and the best English version is the one by former president Herbert Hoover.
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